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In this paper, physical modeling including optical and Casimir forces is adopted in order to analyze a nano-opto-mechanical actuator based on silicon-on-insulator suspended slot waveguides. Numerical simulations based on the finite element method and systematic design rules are presented. Moreover, parametric investigations on

In this paper, physical modeling including optical and Casimir forces is adopted in order to analyze a nano-opto-mechanical actuator based on silicon-on-insulator suspended slot waveguides. Numerical simulations based on the finite element method and systematic design rules are presented. Moreover, parametric investigations on slot waveguide sizes and optical properties are presented, and their influence on the actuator’s features are discussed.
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In this work, we introduce a totally vacuum-free cost-efficient crystalline silicon solar cells. Solar cells were fabricated based on low-cost techniques including spin coating, spray pyrolysis, and screen-printing. A best efficiency of 17.51% was achieved by non-vacuum process with a basic structure of

In this work, we introduce a totally vacuum-free cost-efficient crystalline silicon solar cells. Solar cells were fabricated based on low-cost techniques including spin coating, spray pyrolysis, and screen-printing. A best efficiency of 17.51% was achieved by non-vacuum process with a basic structure of <AI/p+/p−Si/n+/SiO2/TiO2/Ag> CZ-Si p-type solar cells. Short circuit current density (JSC) and open circuit voltage (VOC) of the best cell were measured as 38.1 mA·cm−2 and 596.2 mV, respectively with fill factor (FF) of 77.1%. Suns-Voc measurements were carried out and the detrimental effect of the series resistance on the performance was revealed. It is concluded that higher efficiencies are achievable by the improvements of the contacts and by utilizing good quality starting wafers.
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Biological research increasingly demands the use of non-invasive and ultra-sensitive imaging techniques. The Airyscan technology was recently developed to bridge the gap between conventional confocal and super-resolution microscopy. This technique combines confocal imaging with a 0.2 Airy Unit pinhole, deconvolution and the pixel-reassignment

Biological research increasingly demands the use of non-invasive and ultra-sensitive imaging techniques. The Airyscan technology was recently developed to bridge the gap between conventional confocal and super-resolution microscopy. This technique combines confocal imaging with a 0.2 Airy Unit pinhole, deconvolution and the pixel-reassignment principle in order to enhance both the spatial resolution and signal-to-noise-ratio without increasing the excitation power and acquisition time. Here, we present a detailed study evaluating the performance of Airyscan as compared to confocal microscopy by imaging a variety of reference samples and biological specimens with different acquisition and processing parameters. We found that the processed Airyscan images at default deconvolution settings have a spatial resolution similar to that of conventional confocal imaging with a pinhole setting of 0.2 Airy Units, but with a significantly improved signal-to-noise-ratio. Further gains in the spatial resolution could be achieved by the use of enhanced deconvolution filter settings, but at a steady loss in the signal-to-noise ratio, which at more extreme settings resulted in significant data loss and image distortion.
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We present a new microscope integrating super-resolved imaging using structured illumination microscopy (SIM) with wide-field optically sectioned fluorescence lifetime imaging (FLIM) to provide optical mapping of molecular function and its correlation with biological nanostructure below the conventional diffraction limit. We illustrate this SIM + FLIM capability to map FRET readouts applied to the aggregation of discoidin domain receptor 1 (DDR1) in Cos 7 cells following ligand stimulation and to the compaction of DNA during the cell cycle.
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We demonstrate a multimodal superresolution microscopy technique based on a phase masked excitation beam in combination with spatially filtered detection. The theoretical foundation for calculating the focus from a non-paraxial beam with an arbitrary azimuthally symmetric phase mask is presented for linear and

We demonstrate a multimodal superresolution microscopy technique based on a phase masked excitation beam in combination with spatially filtered detection. The theoretical foundation for calculating the focus from a non-paraxial beam with an arbitrary azimuthally symmetric phase mask is presented for linear and two-photon excitation processes as well as the theoretical resolution limitations. Experimentally this technique is demonstrated using two-photon luminescence from 80 nm gold particle as well as two-photon fluorescence lifetime imaging of fluorescent polystyrene beads. Finally to illustrate the versatility of this technique we acquire two-photon fluorescence lifetime, two-photon luminescence, and second harmonic images of a mixture of fluorescent molecules and 80 nm gold particles with <120 nm resolution (λ/7). Since this approach exclusively relies on engineering the excitation and collection volumes, it is suitable for a wide range of scanning-based microscopies.
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